They won't, period. If it weren't for the hardcore Nintendo fans in Japan and Nintendo's exclusives like Pokemon, Zelda and Mario, they had gone bankrupt ages ago, just like Sega almost did after the Dreamcast fiasco (which was an amazing device btw). They're definitely not going to make their exclusives available on any other platform but Nintendo devices. You could of course think of Nintendo releasing a very own smartphone, but considering how many companies are struggling while trying to be successful in the mobile sector, I highly doubt Nintendo is gonna risk that.

So they risk a business by not going mobile.. they could easily go bankrupt as well... lol

They would also risk their business by entering a battle that they don't specialize with. Nintendo has been successful with handheld consoles that's why they stay on that field. They don't specialize in phones so I doubt they'll do that, especially now there's too much variety.